JP2014100066A - Control device and control unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply system capable of allowing a load to use a current larger than a threshold value which can be a trigger to shut off a distribution line without shutting off the distribution line supplying the power from the commercial power supply to the load.SOLUTION: The power supply system includes: a limiter 46 which is disposed in a distribution line 45 that supplies the power from a commercial AC power source 2 to a DC apparatus and an AC apparatus 6 to shut off the distribution line 45 when a current larger than a contracted current threshold value preset in the distribution line 45 is supplied; a storage battery 16 which is connected closer to the DC apparatus and AC apparatus 6 side than the limiter 46 in the distribution line 45; a discharge circuit 55 that is driven when the power stored in the storage battery 16 is distributed to the DC apparatus and AC apparatus 6; a CT 49 that detects the current under use at the DC apparatus and AC apparatus 6 side rather than the limiter 46; and a control unit 57 that, when the current in use is determined exceeding the contracted current threshold value on the basis of the power consumption detected by the CT 49, drives the discharge circuit 55.

Description

  The present invention relates to a control device and a control unit used for a power supply system including a storage battery.

  Conventionally, for example, as described in Patent Document 1, when a power system that includes a chargeable / dischargeable storage battery and supplies power from a commercial power supply fails, various types of loads are generated by discharging the storage battery. 2. Description of the Related Art A power supply system that supplies power to such devices is known.

JP 2009-159730 A

  Incidentally, the upper limit of the current supplied from the commercial power supply in the power supply system provided in each home is generally determined by a contract with an electric power company. When the load of the household power supply system uses a current exceeding the contracted current (that is, the shut-off threshold), the limiter shuts off the power distribution path and supplies power to the equipment via the power system. The supply is stopped.

  Therefore, when the distribution path is interrupted by such a limiter, the limiter is energized with the devices used in the system narrowed down so that the current used in the load device is less than the contracted current. The power supply from the commercial power supply had to be resumed.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a cutoff threshold that is an opportunity to shut off the distribution path without blocking the distribution path that supplies power from the commercial power source to the load side. An object of the present invention is to provide a control device and a control unit used in a power supply system that can use the above current on the load side.

In the following, means for achieving the above object and its effects are described.
The control device according to claim 1 is provided in a distribution path that supplies power from a commercial power source to a load side, and when the current exceeding the preset cutoff threshold is supplied to the distribution path, A circuit breaker to be interrupted; a storage battery connected to the load side of the circuit breaker in the distribution path; and a discharge means that is driven when distributing the power stored in the storage battery to the load; A charging means that is driven when charging the storage battery; a current detection means that detects a working current in use on the load side of the circuit breaker; and a power generation means that converts natural energy into electric power. The threshold value is a control device used in a power supply system that is set to a value that supplements a current based on power generation by the power generation means at the time of power generation by the power generation means, and the use detected by the current detection means And a control means for driving the discharge means when it is determined that the use current exceeds the cutoff threshold based on the current, and the control means has a smaller amount of power generated by the power generation means than the use current. The power from the commercial power source is controlled to be supplied to the load side, and the use current is equal to or greater than the total current of the current based on the power generation of the power generation means and the cutoff threshold, and the power from the commercial power source The discharge means is driven to distribute the power stored in the storage battery to the load, and the amount of power generated by the power generation means is the usage The gist is to drive the charging means and store the electric power generated by the power generation means in the storage battery when the current is larger than the current.

  According to this configuration, the control means drives the discharge means when it is determined that the use current exceeds the cutoff threshold based on the use current detected by the current detection means. Then, since the electric power stored in the storage battery is distributed to the load, the current supplied from the commercial power source is reduced by the amount distributed from the storage battery. Furthermore, since the storage battery is connected to the load side with respect to the circuit breaker, the power discharged from the storage battery is distributed to the load without passing through the circuit breaker. Therefore, it is possible to cause the load side to use a current equal to or higher than the cutoff threshold value, which is an opportunity to shut off the distribution path, without cutting off the distribution path that supplies power from the commercial power source to the load side.

  In addition, in solar power generation and wind power generation using natural energy such as sunlight and wind, the amount of power generation depends on conditions such as the weather. Therefore, even in the power supply system including the power generation means, the cutoff threshold is set to be larger in preparation for the case where power generation by the power generation means is not performed. However, in general, the cost associated with the use of the commercial power source increases as the cutoff threshold increases. In this respect, according to this configuration, since a current larger than the cutoff threshold can be used on the load side, the cutoff threshold can be set according to the power generation of the power generation means. That is, for example, by setting the cutoff threshold to such an extent that the current generated by the power generation means supplements the current generated by the power generation means, the cutoff threshold is set to such an extent that power can be supplied from the commercial power source to the full load during non-power generation The cost can be reduced compared to

The gist of the control device according to claim 2 is that the control means drives the charging means when the breaker is in a non-breaking state.
According to this configuration, the control unit can store the electric power supplied from the commercial power source in the storage battery by driving the charging unit in a non-interrupted state of the circuit breaker that can supply electric power from the commercial power source to the load side. it can.

  The control device according to claim 3, wherein, when the use current detected by the current detection unit is equal to or less than the cutoff threshold, the control unit is configured to store the storage battery while power is being supplied to the load side. The gist is to drive the charging means so that the battery is charged until the target charging amount is reached.

  A control unit according to claim 4 is a control unit according to any one of claims 1 to 3, and a discharging unit that is driven when distributing the power stored in the storage battery to the load. Charging means driven when charging the storage battery, discharging means driven when distributing the power stored in the storage battery to the load, and converting the input DC power into AC power And when outputting power from the storage battery to an AC load connected to the secondary side of the distribution path from the circuit breaker, via the DC / AC converter The main point is to distribute power.

  According to this configuration, power can be supplied to the AC load by converting the DC power discharged from the battery into AC power by the DC / AC converter. Therefore, even if it is a case where the electric current which AC load uses exceeds a cutoff threshold value, it can suppress that a distribution path is interrupted | blocked.

  According to the present invention, a power supply that can cause a current on the load side to use a current that is equal to or higher than a cutoff threshold that interrupts the distribution path without interrupting the distribution path that supplies power from the commercial power source to the load side. A control device and a control unit used in the system can be provided.

The block diagram of the electric power supply system in this embodiment. The block diagram for demonstrating an AC distribution board and a control unit. The flowchart of an electric power supply system.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments embodying the present invention will be described with reference to FIGS.
As shown in FIG. 1, a house is provided with a power supply system 1 that supplies power to various devices (such as lighting devices, air conditioners, home appliances, and audiovisual devices) installed in the house. The power supply system 1 operates various devices using a commercial AC power source (AC power source) 2 as a commercial power source for home use as power, and also uses the power of a solar cell 3 as a power generation means that generates power from sunlight as natural energy. Is also supplied as power to various devices. The power supply system 1 includes not only a DC device 5 as a DC load that operates by inputting a DC power source (DC power source) but also an AC device 6 as an AC load that operates by inputting an AC power source (AC power source). Supply power.

  The power supply system 1 is provided with a control unit 7 as a distribution board of the system 1 and a DC distribution board (built-in DC breaker) 8. The power supply system 1 is provided with a control unit 9 and a relay unit 10 as devices for controlling the operation of the DC device 5 in the house.

  An AC distribution board 11 for branching an AC power supply is connected to the control unit 7 via an AC power line 12. The control unit 7 is connected to the commercial AC power source 2 through the AC distribution board 11 and is connected to the solar cell 3 through the DC system power line 13. The control unit 7 takes in AC power from the AC distribution board 11 and DC power from the solar cell 3 and converts these powers into predetermined DC power as a device power source. The control unit 7 outputs the converted DC power to the DC distribution board 8 via the DC system power line 14 or to the storage battery 16 as a battery via the DC system power line 15. To store electricity. The control unit 7 can not only take AC power from the AC distribution board 11 but also convert DC power of the solar cell 3 and the storage battery 16 to AC power and supply it to the AC distribution board 11. The control unit 7 exchanges data with the DC distribution board 8 via the signal line 17.

  The DC distribution board 8 is a kind of breaker that supports DC power. The DC distribution board 8 branches the DC power input from the control unit 7 and outputs the branched DC power to the control unit 9 via the DC power line 18 or relays via the DC power line 19. Or output to the unit 10. Further, the DC distribution board 8 exchanges data with the control unit 9 via the signal line 20 and exchanges data with the relay unit 10 via the signal line 21.

  A plurality of DC devices 5, 5... Are connected to the control unit 9. These DC devices 5 are connected to the control unit 9 via a DC supply line 22 that can carry both DC power and data by a pair of lines. The DC supply line 22 superimposes a communication signal for transmitting data by a high-frequency carrier wave on a DC voltage serving as a power source for the DC device, so-called power line carrier communication. Transport to. The control unit 9 acquires the DC power supply of the DC device 5 via the DC power line 18 and controls which DC device 5 based on the operation command obtained from the DC distribution board 8 via the signal line 20. Know what to do. Then, the control unit 9 controls the operation of the DC device 5 by outputting a DC voltage and an operation command to the instructed DC device 5 via the DC supply line 22.

  A switch 23 that is operated when switching the operation of the DC device 5 in the house is connected to the control unit 9 via a DC supply line 22. In addition, a sensor 24 that detects a radio wave transmitted from an infrared remote controller, for example, is connected to the control unit 9 via a DC supply line 22. Therefore, not only the operation instruction from the DC distribution board 8 but also the operation of the switch 23 and the detection of the sensor 24, a communication signal is sent to the DC supply line 22 to control the DC device 5.

  A plurality of DC devices 5, 5... Are connected to the relay unit 10 via individual DC power lines 25. The relay unit 10 acquires the DC power supply of the DC device 5 through the DC power line 19 and determines which DC device 5 is to be operated based on an operation command obtained from the DC distribution board 8 through the signal line 21. To grasp. The relay unit 10 controls the operation of the DC device 5 by turning on / off the power supply to the DC power line 25 with respect to the instructed DC device 5 using a built-in relay. In addition, a plurality of switches 26 for manually operating the DC device 5 are connected to the relay unit 10, and the DC power line 25 is turned on and off by the relay by operating the switch 26, thereby enabling the DC unit 5 to operate the DC unit 5. The device 5 is controlled.

  The DC distribution board 8 is connected to a DC outlet 27 built in a house in the form of a wall outlet or a floor outlet, for example, via a DC power line 28. If a plug (not shown) of a DC device is inserted into the DC outlet 27, DC power can be directly supplied to the device.

  Further, a power meter 29 capable of remotely metering the amount of use of the commercial AC power supply 2 is connected between the commercial AC power supply 2 and the AC distribution board 11. The power meter 29 is equipped with not only a function of remote meter reading of the amount of commercial power used, but also a function of power line carrier communication and wireless communication, for example. The power meter 29 transmits the meter reading result to an electric power company or the like via power line carrier communication or wireless communication.

  The power supply system 1 is provided with a network system 30 that enables various devices in the home to be controlled by network communication. The network system 30 is provided with a home server 31 as a control unit of the system 30. The home server 31 is connected to a management server 32 outside the home via a network N such as the Internet, and is connected to a home device 34 via a signal line 33. The in-home server 31 operates using DC power acquired from the DC distribution board 8 via the DC power line 35 as a power source.

  A control box 36 that manages operation control of various devices in the home by network communication is connected to the home server 31 via a signal line 37. The control box 36 is connected to the control unit 7 and the DC distribution board 8 via the signal line 17 and can directly control the DC device 5 via the DC supply line 38. For example, a gas / water meter 39 capable of remotely metering the amount of gas used or the amount of water used is connected to the control box 36 and also connected to the operation panel 40 of the network system 30. The operation panel 40 is connected to a monitoring device 41 including, for example, a door phone slave, a sensor, and a camera.

  When the in-home server 31 inputs an operation command for various devices in the home via the network N, the home server 31 notifies the control box 36 of the instruction, and operates the control box 36 so that the various devices operate in accordance with the operation command. . The in-home server 31 can provide various information acquired from the gas / water meter 39 to the management server 32 through the network N, and accepts from the operation panel 40 that the monitoring device 41 has detected an abnormality. This is also provided to the management server 32 through the network N.

  Next, the AC distribution board 11 and the control unit 7 will be described with reference to FIG. In the power supply system 1 of the present embodiment, the distribution path 45 that supplies power from the commercial AC power supply 2 to the AC distribution board 11 is connected to the first line L1 and the second line L2 with 100V AC from the commercial AC power supply 2. While the voltage is applied, the third line L3 is 0V.

  As shown in FIG. 2, a limiter 46, a main breaker 47, and a branch breaker 48 as a circuit breaker are connected to the distribution path 45 in order from the primary side that is the commercial AC power supply 2 side in the AC distribution board 11. Is provided. The distribution path 45 between the limiter 46 and the main breaker 47 has an AC current detector (hereinafter referred to as “CT”) as current detection means for acquiring currents in the first line L1 and the second line L2, respectively. 49) is provided.

  The limiter 46 is supplied with a current exceeding a contract current threshold value K1 (for example, 20 A at 100 V, but half the current at 200 V) as a cutoff threshold set based on a contract with an electric power company that provides the commercial AC power supply 2. In this case, the power distribution path 45 is shut off. That is, when power is used on the secondary side to which the DC device 5 and the AC device 6 are connected, a current corresponding to the magnitude of the load flows through the limiter 46. When a current larger than the contract current threshold value K1 is supplied from the commercial AC power supply 2, the bimetal (not shown) provided in the limiter 46 generates heat and curves according to the current, and disconnects the contact. The supply of power from the commercial AC power supply 2 is stopped. The limiter 46 cuts off the power distribution path 45 when the total current A of the first line L1 and the second line L2 exceeds the contract current threshold value K1.

  Further, the main breaker 47 connected to the secondary side of the limiter 46 cuts off the distribution path 45 when an abnormal current flows due to leakage or short circuit on the secondary side. Further, the branch breaker 48 is provided so as to individually correspond to the branch path 51 branched to correspond to each AC device 6 or each room of the house. The branch breaker 48 individually blocks each branch path 51 when the current supplied via each branch path 51 exceeds the branch current threshold value K2 set to a value smaller than the contract current threshold value K1.

  On the other hand, the control unit 7 includes a branch breaker 48, an AC / DC converter 52, a DC / AC inverter 53 as a DC / AC converter, a DC / DC converter 54, a discharge circuit 55 as a discharge means, and a charge as a charge means. A control device 57 is provided as control means for controlling the circuit 56 and distributing current to the DC device 5 and the AC device 6. That is, the control device 57 controls the current A supplied from the commercial AC power supply 2 based on the detection result of CT49.

  Specifically, the AC / DC converter 52 takes in AC power supplied from the commercial AC power supply 2 through the AC distribution board 11, converts it into DC power, and outputs it to the DC distribution board 8. Further, the DC / DC converter 54 transforms the DC power generated by the solar cell 3 into a voltage that can be used by the DC device 5 and outputs the voltage to the DC distribution board 8.

  The charging circuit 56 outputs DC power to the storage battery 16 to charge the storage battery 16. That is, the DC power supplied from the commercial AC power source 2 and converted by the AC / DC converter 52 and the DC power generated by the solar cell 3 and transformed by the DC / DC converter 54 are used by the charging circuit 56 to the storage battery 16. By outputting, the battery 16 is also charged. Then, the discharge circuit 55 outputs DC power from the storage battery 16 by discharging the charged storage battery 16.

  Furthermore, the DC / AC inverter 53 converts the DC power output accompanying the discharge of the storage battery 16 and the DC power generated by the solar battery 3 into AC power. The converted AC power is applied to the AC device 6 via the branch path 51 to which the branch breaker 48 is connected.

  Next, the operation of the control device used in the power supply system 1 configured as described above will be described with reference to the flowchart shown in FIG.

  First, the control device 57 obtains the current A supplied from the commercial AC power supply 2 by summing the currents of the first line L1 and the second line L2 detected by the CT 49 in step S110. Then, in step S120, the control device 57 determines whether or not the acquired current A exceeds the contract current threshold value K1 at which the limiter 46 blocks the power distribution path 45. In general, the limiter 46 is designed to shut off the power distribution path 45 when a current equal to or greater than the contract current threshold value K1 is supplied for a certain period of time.

  Therefore, when the current A is equal to or less than the contract current threshold value K1 (step S120: YES), the control device 57 determines that the possibility that the distribution path 45 is interrupted is low, and the storage battery 16 is subsequently charged with the target charge amount. Is determined (step S130). In addition, the storage battery 16 repeats the full charge which accumulate | stores until a full charge capacity | capacitance, deterioration accelerates | stimulates and the capacity | capacitance which can be stored decreases. Therefore, in the present embodiment, a charge amount smaller than the full charge capacity (for example, 80% with respect to full charge) is set as the target charge amount.

  When the target charge amount is charged in the storage battery 16, the control device 57 determines that the storage battery 16 does not need to be charged (step S130: YES). Note that the control device 57 repeatedly executes the flowchart shown in FIG. 3 while the DC device 5 or the AC device 6 is connected to the secondary side and power is supplied from the commercial AC power supply 2. Therefore, when determining that charging of the storage battery 16 is not necessary in step S130 (step S130: YES), the control device 57 returns to step S110, executes the process of step S110 again, and acquires the current A.

  On the other hand, when the charge amount of the storage battery 16 is less than the target charge amount (step S130: NO), the control device 57 determines that the storage battery 16 needs to be charged, and the branch breaker 48, the AC / DC converter 52, the charge The battery 56 is charged by controlling the circuit 56 (step S140). That is, the power supplied from the commercial AC power supply 2 is distributed into power supplied to the AC device 6 by the branch breaker 48 and power converted to DC power by the AC / DC converter 52. The DC power converted by the AC / DC converter 52 is supplied to each DC device 5 via the DC distribution board 8 and is output to the storage battery 16 by the charging circuit 56 to charge the storage battery 16. Then, in order to repeatedly execute the process of the flowchart, the control device 57 returns the process to step S110 and acquires the current A again (step S110).

  On the other hand, if the current A is larger than the contract current threshold K1 in step S120 (step S120: NO), the control device 57 determines that the current A exceeds the contract current threshold K1, and then controls the discharge circuit 55 to control the storage battery. 16 is discharged (step S150). Then, since the electric power discharged from the storage battery 16 is supplied to the DC device 5 via the DC distribution board 8, the AC power supplied from the commercial AC power supply 2 is supplied to the AC device 6. Therefore, compared with the case where the DC device 5 and the AC device 6 are driven based on the power supplied from the commercial AC power source 2, the power supplied from the commercial AC power source 2 is reduced and the current A is also reduced. The blocking of the 46 distribution paths 45 is suppressed, and the non-blocking state is maintained. When the load on the AC device 6 is large, DC power discharged from the storage battery 16 is converted into AC power by the DC / AC inverter 53 and supplied to the AC device 6. Then, in order to repeatedly execute the process of the flowchart, the control device 57 returns the process to step S110 and acquires the current A again (step S110).

Next, the operation of the control device used in the power supply system 1 during power generation in which the solar cell 3 generates power and supplies power will be described.
First, the control device 57 controls the DC / DC converter 54 to transform the DC power generated by the solar cell 3 and output it to the DC distribution board 8 and also controls the DC / AC inverter 53 and the branch breaker 48. Then, the converted AC power is supplied to the AC device 6.

  The control device 57 controls the charging circuit 56 to control the DC when the amount of power generated by the solar cell 3 is larger than the amount of power used by the DC device 5 and the AC device 6 connected to the power supply system 1. DC power output from the DC converter 54 is stored in the storage battery 16.

  When the current A detected by the CT 49 becomes larger than the contract current threshold value K1, the control device 57 controls the discharge circuit 55 to discharge the power stored in the storage battery 16. That is, when the DC device 5 and the AC device 6 connected to the power supply system 1 use a current that is equal to or greater than the total current of the current based on the power generation of the solar cell 3 and the contract current threshold value K1, power is supplied from the storage battery 16. Since it is supplied, the current A detected by the CT 49 is reduced.

According to the above embodiment, the following effects can be obtained.
(1) The control device 57 drives the discharge circuit 55 when it is determined that the current A exceeds the contract current threshold K1 based on the current A detected by the CT 49. Then, since the electric power stored in the storage battery 16 is distributed to the DC device 5 and the AC device 6, the current A supplied from the commercial AC power supply 2 decreases by the amount distributed from the storage battery 16. Become. Furthermore, since the storage battery 16 is connected to the DC device 5 and the AC device 6 side of the limiter 46, the electric power discharged from the storage battery 16 is distributed to the DC device 5 and the AC device 6 without passing through the limiter 46. Therefore, the DC device supplies a current equal to or greater than the contract current threshold value K1 that triggers the disconnection of the power distribution path 45 without interrupting the power distribution path 45 that supplies power from the commercial AC power supply 2 to the DC device 5 and the AC device 6 side. 5 and the AC device 6 side.

  (2) By converting DC power discharged from the storage battery 16 into AC power by the DC / AC inverter 53, power can be supplied from the storage battery 16 to the AC device 6. Therefore, even if the current used by the AC device 6 exceeds the contract current threshold value K1, it is possible to prevent the distribution path 45 from being interrupted by supplying power from the storage battery 16.

(3) By using a chargeable / dischargeable storage battery 16 as a battery serving as a backup power source, it is possible to save the trouble of replacing the battery.
(4) The control device 57 is supplied from the commercial AC power source 2 by driving the charging circuit 56 in a non-cut-off state of the limiter 46 that can supply power from the commercial AC power source 2 to the DC device 5 and the AC device 6 side. The stored power can be stored in the storage battery 16.

  (5) In solar power generation using solar light, the amount of power generation depends on conditions such as the weather. Therefore, in the conventional power supply system, even if the solar battery 3 is provided, the contract current threshold value K1 is set to be larger in preparation for the case where power generation by the solar battery 3 is not performed. However, in general, the cost associated with the use of the commercial AC power supply 2 increases as the contract current threshold value K1 increases. In that respect, since the current A larger than the contract current threshold K1 can be used on the DC device 5 and AC device 6 side, the contract current threshold K1 can be set in accordance with the power generation of the solar cell 3. That is, for example, when the solar cell 3 generates power, the contract current threshold value K1 is set to such an extent that the solar cell 3 compensates for the current based on the power generation, so that power is supplied from the commercial AC power source 2 to the DC device 5 and the AC device 6 during non-power generation. The cost can be reduced compared to the case where the contract current threshold value K1 is set to such an extent that can be supplied.

In addition, you may change the said embodiment as follows.
-You may provide the electric power generation means using natural energy, such as the wind power generation which rotates a blade | wing with a wind, and geothermal power generation using geothermal, and hydroelectric power generation using hydropower. Moreover, it is good also as a structure which is not provided with these electric power generation means and the solar cell 3. FIG.

  -Since the battery has an upper limit in the amount of electricity stored, a large battery with a large amount of electricity stored is required when discharging over a long period of time. Therefore, for example, a generator capable of generating power arbitrarily may be provided, such as a fuel cell that generates power by reacting hydrogen contained in gas with oxygen. And the enlargement of a battery can be suppressed by using a generator and a battery together. That is, for example, by discharging the battery as a connection until the generator starts power generation, when the power used increases, the power can be supplied quickly, and blocking of the distribution path 45 by the limiter 46 can be suppressed. . Furthermore, even when a battery with a small amount of stored electricity is used, by switching to power supply from the generator, it is possible to extend the time during which a current exceeding the contract current threshold value K1 can be supplied.

  When the electric power more than the amount of electric power used by the DC device 5 and the AC device 6 is generated by power generation means such as a fuel cell or wind power generation, the surplus power may be stored in the storage battery 16. In other words, when the power generation means is provided, the storage battery 16 may be charged regardless of whether the distribution path 45 is in the cut-off state or the non-cut-off state.

-As the battery, a primary battery that can only be discharged may be provided, and the discharged primary battery may be replaced with a new one.
The direct current power discharged from the storage battery 16 may be supplied only to the DC device 5 without providing the DC / AC inverter 53.

  A discharge start threshold (for example, 18 A at 100 V) set to be equal to or less than the contract current threshold K1 may be set in advance, and the battery 16 may be discharged when the current A exceeds the discharge start threshold. Further, when the current A becomes equal to or greater than the contract current threshold value K1, it may be determined that the contract current threshold value K1 has been exceeded and the storage battery 16 may be discharged.

  -You may provide the detection means which each detects the use electric current of DC apparatus 5, and the use electric current of AC apparatus 6 separately. Then, the AC power output from the commercial AC power supply 2 is supplied to the AC device 6, the DC power output from the storage battery 16 is supplied to the DC device 5, and the current used by the AC device 6 is greater than the contract current threshold K 1. In the case of increasing the number, the DC power may be converted into AC power and supplied to the AC device 6. Since loss occurs when DC power and AC power are converted, power loss can be reduced and efficiency can be improved by reducing conversion between DC power and AC power.

  DESCRIPTION OF SYMBOLS 1 ... Electric power supply system, 2 ... Commercial alternating current power supply (commercial power supply), 3 ... Solar cell (electric power generation means), 5 ... DC equipment (load), 6 ... AC equipment (load, alternating current load), 7 ... Control unit, 16 ... storage battery (battery), 45 ... distribution path, 46 ... limiter (breaker), 49 ... alternating current detector (current detection means), 53 ... DC / AC inverter (DC / AC converter), 55 ... discharge circuit ( Discharging means), 56 ... Charging circuit (charging means), 57 ... Control device (control means), A ... Current, K1 ... Contract current threshold (cutoff threshold).

Claims (4)

A circuit breaker that is provided in a power distribution path that supplies power from a commercial power source to the load side, and that interrupts the power distribution path when a current that is greater than or equal to a preset shutoff threshold is supplied to the power distribution path;
A storage battery connected to the load side of the circuit breaker in the distribution path;
Discharging means that is driven when the power stored in the storage battery is distributed to the load;
Charging means driven when charging the storage battery;
Current detection means for detecting a current used in use on the load side of the circuit breaker;
Power generation means for converting natural energy into electric power,
The cutoff threshold is a control device used in a power supply system that is set to a value that supplements a current based on power generation by the power generation means during power generation by the power generation means,
When it is determined that the use current exceeds the cutoff threshold based on the use current detected by the current detection means, the control means for driving the discharge means,
The control means includes
When the amount of power generated by the power generation means is less than the current used, control is performed so that power from the commercial power supply is supplied to the load side,
The discharge means is driven when it is determined that the use current is equal to or greater than the total current of the current based on the power generation of the power generation means and the cutoff threshold, and that power from the commercial power supply is supplied beyond the cutoff threshold And distributes the electric power stored in the storage battery to the load,
A control device characterized in that when the amount of power generated by the power generation means is greater than the operating current, the charging means is driven to store the power generated by the power generation means in the storage battery. The control device according to claim 1, wherein the control unit drives the charging unit when the circuit breaker is in a non-breaking state. The control means is charged until the storage battery reaches a target charge amount while electric power is supplied to the load side when the use current detected by the current detection means is less than or equal to the cutoff threshold. The control device according to claim 2, wherein the charging unit is driven. The control device according to any one of claims 1 to 3,
Discharging means that is driven when the power stored in the storage battery is distributed to the load;
Charging means driven when charging the storage battery;
Discharging means that is driven when the power stored in the storage battery is distributed to the load;
A DC / AC converter that converts the input DC power into AC power and outputs the AC power;
When distributing from the storage battery to an AC load connected to the secondary side of the distribution path from the circuit breaker, the control unit distributes power via the DC / AC converter.